Hearing Loss and Coronary Heart Disease

OUR FIRST study in 1960-1961 1 among members of the Mabaan tribe in southeast Sudan revealed their superior hearing. At 500 to 6,000 cps hearing is significantly more acute in all Mabaans aged 10 through 70 years than in people of the same age who live in industrial areas of the United States 2 (Fig 1). Except for the bleat of a goat and other sounds of nature, the Mabaans live in a dramatically quiet, almost silent atmosphere. The bombardment of excessive noise in our culture and the virtual absence of such in theirs could be one of the factors responsible for their superior hearing. Generally, hearing loss and increase in blood pressure occur with aging in healthy persons of the United States, 3 while the Mabaans' systolic and diastolic blood pressures remain the same at 75 as at 15 years of age, and coronary heart disease is unknown in